AU2011265389A1 - Boat Hull Protection System - Google Patents

Abstract

Abstract A system 10 of protecting a boat hull from marine growth, the system 10 5 comprising a pen 12 made of substantially waterproof material for holding a sufficient volume of water so that a boat 14 can be moved into the pen 12 with the boat hull floating in the volume of water. The system 10 also comprises a UV light sterilizing means 18 for sterilizing substantially the whole volume of water held in the pen 12 whereby, in use, marine growth is 10 inhibited from forming on the hull of the boat 14. A method of protecting a boat hull from marine growth is also described. Figure to accompany Abstract: Figure 1

Description

ORIGINAL AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Invention title: "BOAT HULL PROTECTION SYSTEM" Applicant: CAMERON MCLEOD Associated Provisional Application No.: 2010905592 The following statement is a full description of the invention, including the best method of performing it known to me: 2 "BOAT HULL PROTECTION SYSTEM" Field of the Invention The present invention relates to a boat hull protection system and method 5 and relates particularly to such a system and method for protecting a boat hull from marine growth. Background to the Invention Marine growth on the hulls of boats is a costly problem for small boat owners. 10 Barnacles, algae and bacteria adhere to the hull of the boat causing damage to the hull surface and producing drag in the water. Marine growth also fowls the propeller and drive shaft of the boat potentially causing thousands of dollars of damage. Barnacles are a species of shell fish which attach themselves to surfaces, such as the hulls of docked boats, where they rapidly 15 multiply as they absorb nutrients from the water. So called 'acorn' barnacles are particularly problematic as they are extremely difficult to remove and damage the surface of the boat hull. Other marine growth, including algae and bacterial growth can also cause damage and fowling. A common approach to the problem of marine growth is to apply anti-fowling 20 agent to the boat hull which repels and/or inhibits the growth of barnacles, algae and bacteria. However the anti-fowling agents commonly used are extremely toxic to other marine life and environmentally undesirable. Australian Innovation Patent No 2003100664 by Sea Pen Holdings Pty Ltd describes a boat hull protection apparatus in which a waterproof sheet is 25 shaped and dimensioned to enclose at least part of the hull. The water between the waterproof sheet and the hull is pumped out so that the sheet adheres to the hull to keep the hull dry and clean and thus protect it from marine growth. One difficulty with the system of Sea Pen is preventing water from re-entering the space between the hull and the water-proof sheet. 30 3 The present invention was developed with a view to providing a boat hull protection system and method that does not use toxic anti-fowling agents and that is simple to use and effective for inhibiting marine growth on boat hulls. 5 References to prior art in this specification are provided for illustrative purposes only and are not to be taken as an admission that such prior art is part of the common general knowledge in Australia or elsewhere. 10 Summary of the Invention According to one aspect of the present invention there is provided a system of protecting a boat hull from marine growth, the system comprising: a pen made of substantially waterproof material for holding a sufficient volume of water so that a boat can be moved into the pen with the boat hull 15 floating in the volume of water; and, a sterilizing means for sterilizing substantially the whole volume of water held in the pen whereby, in use, marine growth is inhibited from forming on the hull of the boat. Preferably the sterilizing means comprises a UV light sterilizing means. 20 Preferably the sterilizing means further comprises a water pump for pumping the water held in the pen through the UV light sterilizing means. Advantageously the water pump is a submersible pump which is located within the volume of water held in the pen. Preferably a plurality of UV light sterilizing means is provided to treat the 25 whole volume of water in the pen in a reasonably short length of time. Typically each UV light sterilizing means comprises a plurality of electric UV light fluorescent tubes located in a double-pass water jacket wherein, in use, the water passing through the UV light sterilizing means receives a double 4 dose of UV light radiation to kill substantially all of the barnacles, algae, bacteria and other micro-organisms in the water. Preferably the pen comprises a shroud made of waterproof material which is supported on a frame. Typically the frame is made from PVC pipes arranged 5 to form a rectangular frame with two side frame portions and two end frame portions. Advantageously the PVC pipes of the frame are sealed at each end so that the air trapped inside makes them sufficiently buoyant to float on the surface of the water whilst supporting the shroud. Preferably the two side frame portions of the frame each comprise first and second sections 10 connected together by a flexible joint, and wherein the first sections of each side portion together with the end portion can be partially filled with water to open an entry/exit gate of the pen. Preferably the shroud is of rectangular shape when viewed in plan, but is of semi-circular shape when viewed end-on, so as to effectively form a half 15 cylinder, with a draught adapted to easily receive the hull of a boat floating in the pen. Preferably all four sides of the shroud are provided with sleeve portions for receiving the PVC pipes of the frame therein. According to another aspect of the present invention there is provided a method of protecting a boat hull from marine growth, the method comprising 20 the steps of: moving the boat into a pen made of substantially waterproof material and holding a sufficient volume of water so that the boat hull floats in the volume of water; and, sterilizing substantially the whole volume of water held in the pen whereby, in 25 use, marine growth is inhibited from forming on the hull of the boat. Preferably the step of sterilising substantially the whole volume of water involves pumping the water trapped within the pen through a UV light sterilizing means until all of the algae, barnacles and other micro-organisms in the water have been killed. Optionally the water within the shroud can be 5 periodically pumped through the UV light sterilizing means to keep the water in a sterile condition. Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be 5 understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. Likewise the word "preferably" or variations such as "preferred", will be understood to imply that a stated integer or group of integers is desirable but not essential to the working of the invention. 10 Brief Description of the Drawings 15 The nature of the invention will be better understood from the following detailed description of several specific embodiments of a boat hull protection system and method, given by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a top perspective view of a preferred embodiment of a boat 20 hull protection system according to the present invention; Figure 2 is a top perspective view of the pen of the boat hull protection system of Figure 1; Figures 3(a) and (b) are a top plan view and side elevation respectively of a frame for the pen illustrated in Figure 2; 25 Figures 4(a), (b) and (c) are a top plan view, rear and front elevation respectively of a waterproof shroud for the pen illustrated in Figure 2; Figure 5 is a top plan view of the boat hull protection system of Figure 1 moored to a boat jetty with a boat floating in the pen; 6 Figures 6(a) and (b) are side elevations of the boat hull protection system of Figure 1 illustrating schematically how a boat can be moved into or out of the pen; Figure 7 is a schematic diagram illustrating the hydraulic circuit for the 5 sterilising means of the boat hull protection system of Figure 1; and, Figure 8 is a functional block circuit diagram of the remote controller for the boat hull protection system of Figure 1. 10 Detailed Description of Preferred Embodiments A preferred embodiment of the boat hull protection system 10 in accordance with the invention, as illustrated in Figures 1 to 8, comprises a pen 12 made of substantially waterproof material for holding a sufficient volume of water so that a boat 14 (see Figures 5 and 6) can be moved into the pen 12 with the 15 boat hull floating in the volume of water. A sterilizing means 16 is provided for sterilizing substantially the whole volume of water held in the pen 12 whereby, in use, marine growth is inhibited from forming on the hull of the boat 14. The waterproof material keeps the volume of water in the pen 12 isolated from the water outside the pen. The sterilizing means 16 kills any 20 barnacles, algae and bacteria present in the volume of water held in the pen 12 so that the hull of the boat remains substantially free of any marine growth. Preferably the sterilizing means 16 comprises a UV light sterilizing means 18. As can be seen most clearly in Figure 7, there are preferably two UV light 25 sterilizing means 18 to treat the whole volume of water in the pen 12 in a reasonably short length of time. Each UV light sterilizing means 18 preferably comprises a pair of 55 Watt electric UV light fluorescent tubes located in a double-pass water jacket 22. A ballast unit 20 for the light tubes is also provided. The double-pass jacket 22 ensures that the water passing through 30 7 the UV light sterilizing means 18 receives a double dose of UV light radiation to kill substantially all of the barnacles, algae, bacteria and other micro organisms in the water, before passing out through water return outlets 26. Preferably the sterilizing means 16 further comprises a water pump 24 for 5 pumping the water held in the pen 12 through the UV light sterilizing means 18. Advantageously the pump is a submersible pump 24 which is located within the volume of water held in the pen 12. As can be seen more clearly in Figure 1, the submersible pump 24 is preferably located near the bottom of the pen 12 and the water return outlets are preferably located adjacent the 10 top of the pen 12 so that there is a good circulation of the whole volume of water in the pen 12 through the UV light sterilization means 18. The operation of the sterilizing means 16 is controlled by the remote control box 30 which is preferably incorporated in the system 10. Figure 8 is a functional block diagram of a typical control circuit housed in remote control 15 box 30. A control unit 32 controls the operation of the UV light fluorescent tubes 20, the submersible pump 24 and a compressor 34 via relays and terminals 36. Transformer 38 and circuit breakers 40 are used to convert the 240 Volt supply power to 120 Volt power for the control unit 32. Compressor 34 provides compressed air to operate an entry/exit gate 44 for the pen, as 20 will be described further below. The pen 12 preferably comprises a shroud 46 made of waterproof material, such as a flexible plastics material, which is supported on a frame 48, as shown in Figure 2. Frame 48 is preferably made from PVC pipes arranged to form a rectangular frame, as illustrated in Figure 3, with two side frame 25 portions 50 and two end frame portions 54. The PVC pipes of frame 48 are sealed at each end so that the air trapped inside makes them sufficiently buoyant to float on the surface of the water whilst supporting the shroud 46. Preferably two side frame portions 50 of the frame 48 comprise first and second sections 50a and 50b respectively, connected together by a flexible 30 joint 52. As will be described further below, the first sections 50a of each side 8 portion 50 together with the end portion 54a can be partially filled with water to open the entry/exit gate 44. Shroud 46 is preferably made of vinyl and is of rectangular shape when viewed in plan, as shown in Figure 4(a), but is of semi-circular shape when 5 viewed end-on, as shown in Figures 4(b) and (c). The shape of the shroud is effectively a half cylinder. The shroud 46 is preferably designed with a draught adapted to easily receive the hull of a boat floating in the pen 12 therein, as shown in Figure 6(a). All four sides of the shroud 46 are provided with sleeve portions 56 for receiving the PVC pipes of the frame 48 therein. 10 Several mooring connection points 58 are provided for mooring the system 10 to a boat jetty (see also Figure 5). The entry/exit gate 44 includes water/air drain hoses 60 (see Figure 1) for draining water and air from the front end section 62 of the frame 48, which comprises the side frame portions 50a and the front end frame portion 54a. 15 When the boat 14 approaches the pen 12, a hand held remote control activates a "dump valve" (not illustrated) in the remote control box 30.The compressor 34 creates a vacuum in the PVC piping of the front end section 62. Water from the pen is drawn into the PVC piping through the water/air drain hoses 60, filling the PVC piping until the front end section 62 loses its 20 buoyancy and automatically begins to submerge. The front end section 62 is able to pivot on the flexible joints 52 until it reaches its fully submerged position, as shown in Figure 6(b). The boat 14 can now enter the pen 12, either by reversing in or going in a forwards direction through the entry/exit gate 44. To close the entry/exit gate 44, the compressor 34 is reversed to 25 pump air back into the PVC piping of the front end section 62 to restore its buoyancy. The front end section 34 will rise back to its horizontal position to return the entry/exit gate 44 to its closed position, as shown in Figure 6(a). The method of protecting a boat hull from marine growth will now be described with reference to the accompanying drawings. The method 30 comprises the steps of moving the boat 14 into the pen 12. Preferably this 9 involves opening the entry/exit gate 44 in the manner already described above. However other methods of getting the boat into the pen 12 may also be employed. For example, instead of only the front end section 62 automatically submerging, the whole frame 48 may automatically submerge 5 to permit the boat to move into the pen 12. The method then involves the step of sterilizing substantially the whole volume of water held in the pen 12 whereby, in use, marine growth is inhibited from forming on the hull of the boat. This preferably involves pumping the water trapped within the shroud 46 or pen 12 through the two 10 UV light sterilizing means 18 until all of the algae, barnacles and other micro organisms in the water have been killed. If necessary the water within the shroud can be periodically pumped through the UV light sterilizing means 18 to keep the water in a sterile condition. However once substantially the whole volume of water within the pen 12 has been sterilized the boat can remain in 15 the pen 12 indefinitely without the risk of marine growth forming on the hull. Optional extra features for the system 10 may include electric lights on the edges of the pen to clearly mark the location of the pen 12. Oil and fuel socks may also be incorporated to absorb any oil or marine fuel that may be in the water trapped within the shroud 46. 20 Now that preferred embodiments of the boat hull protection system and method have been described in detail, it will be apparent that the described embodiments provide a number of advantages over the prior art, including the following: 25 (i) A boat hull can be fully protected from marine growth without using environmentally harmful and toxic anti-fowling agents. (ii) The system and method can be fully automated avoiding the need for any manual handling.

10 (iii) The system and method can be scaled up to accommodate any size boat hull. It will be readily apparent to persons skilled in the relevant arts that various 5 modifications and improvements may be made to the foregoing embodiments, in addition to those already described, without departing from the basic inventive concepts of the present invention. For example, it will be appreciated that the pen may be constructed in a variety of ways using a different design and different materials from that described, such as an 10 aluminium frame with its own buoyancy control mechanism, instead of PVC piping. Therefore, it will be appreciated that the scope of the invention is not limited to the specific embodiments described.

Claims (17)

1. A system of protecting a boat hull from marine growth, the system comprising: 5 a pen made of substantially waterproof material for holding a sufficient volume of water so that a boat can be moved into the pen with the boat hull floating in the volume of water; and, a sterilizing means for sterilizing substantially the whole volume of water held in the pen whereby, in use, marine growth is inhibited from forming on the 10 hull of the boat.

2. A system of protecting a boat hull as defined in claim 1, wherein the sterilizing means comprises a UV light sterilizing means.

3. A system of protecting a boat hull as defined in claim 2, wherein the sterilizing means further comprises a water pump for pumping the water held 15 in the pen through the UV light sterilizing means.

4. A system of protecting a boat hull as defined in claim 3, wherein the water pump is a submersible pump which is located within the volume of water held in the pen.

5. A system of protecting a boat hull as defined in any one of claims 2 to 4, 20 wherein a plurality of UV light sterilizing means is provided to treat the whole volume of water in the pen in a reasonably short length of time.

6. A system of protecting a boat hull as defined in claim 5, wherein each UV light sterilizing means comprises a plurality of electric UV light fluorescent tubes located in a double-pass water jacket wherein, in use, the water 25 passing through the UV light sterilizing means receives a double dose of UV light radiation to kill substantially all of the barnacles, algae, bacteria and other micro-organisms in the water. 12

7. A system of protecting a boat hull as defined in any one of the preceding claims, wherein the pen comprises a shroud made of waterproof material which is supported on a frame.

8. A system of protecting a boat hull as defined in claim 7, wherein the frame 5 is made from PVC pipes arranged to form a rectangular frame with two side frame portions and two end frame portions.

9. A system of protecting a boat hull as defined in claim 8, wherein the PVC pipes of the frame are sealed at each end so that the air trapped inside makes them sufficiently buoyant to float on the surface of the water whilst 10 supporting the shroud.

10. A system of protecting a boat hull as defined in claim 8, wherein the two side frame portions of the frame each comprise first and second sections connected together by a flexible joint, and wherein the first sections of each side portion together with the end portion can be partially filled with water to 15 open an entry/exit gate of the pen.

11. A system of protecting a boat hull as defined in claim 8, wherein the shroud is of rectangular shape when viewed in plan, but is of semi-circular shape when viewed end-on, so as to effectively form a half cylinder, with a draught adapted to easily receive the hull of a boat floating in the pen. 20

12. A system of protecting a boat hull as defined in claim 11, wherein all four sides of the shroud are provided with sleeve portions for receiving the PVC pipes of the frame therein.

13. A method of protecting a boat hull from marine growth, the method comprising the steps of: 25 moving the boat into a pen made of substantially waterproof material and holding a sufficient volume of water so that the boat hull floats in the volume of water; and, sterilizing substantially the whole volume of water held in the pen whereby, in use, marine growth is inhibited from forming on the hull of the boat. 13

14. A method of protecting a boat hull from marine growth as defined in claim 13, wherein the step of sterilising substantially the whole volume of water involves pumping the water trapped within the pen through a UV light sterilizing means until all of the algae, barnacles and other micro-organisms 5 in the water have been killed.

15. A method of protecting a boat hull from marine growth as defined in claim 14, wherein if necessary the water within the shroud can be periodically pumped through the UV light sterilizing means to keep the water in a sterile condition. 10

16. A system of protecting a boat hull from marine growth substantially as herein described with reference to and as illustrated in any one or more of the accompanying drawings.

17. A method of protecting a boat hull from marine growth substantially as herein described with reference to and as illustrated in any one or more of 15 the accompanying drawings. Dated this 2 0 th day of December 2011 20 Cameron McLeod by his Patent Attorneys Janet Stead & Associates